We study the radio galaxies with known redshift detected by Fermi satellite after 10 years of data (4FGL-DR2). use a one-zone leptonic model to fit quasi-simultaneous multiwavelength these and distributions derived physical parameter as function black hole mass accretion disk luminosity. The main results are follows. (1) find that jet kinetic power most can be explained hybrid based on ADAFs su...

We use lookback time versus redshift data from galaxy clusters (Capozziello et al. 2004) and passively evolving galaxies (Simon et al. 2005), in combination with the WMAP determination of the age of the Universe, to constrain dark energy cosmological model parameters. Current lookback time data provide interesting and moderately restrictive constraints on cosmological parameters. When used join...

CCD – photometry is presented for 20 dIrr galaxies situated in the nearby complexes CenA/M83, and CVnI as well as in the general field of the Local Volume. We present integrated magnitudes of the galaxies in B, V, Ibands and also surface brightness profiles to a median isophote μB ∼ 28 mag sq. arcsec . The popular Sersic parameterization of surface brightness profiles generally does a poor job ...

We present the first results of an ongoing project to study the morphological, kinematical, dynamical, and chemical properties of satellite galaxies of external giant spiral galaxies. The sample of objects has been selected from the catalogue by Zaritsky et al. (1997). The paper analyzes the morphology and structural parameters of a subsample of 60 such objects. The satellites span a great vari...

Based on the catalog of merging galaxies in the Early Data Release (EDR) of the Sloan Digital Sky Survey (SDSS), the differences of star formation history between merging galaxies and field galaxies are studied statistically by means of three spectroscopic indicators the 4000-Å break strength, the Balmer absorption-line index, and the specific star formation rate. It is found that for early-typ...

We present two pieces of evidence supporting the hypothesis that the bright [O III] λ5007 sources found in Virgo’s intracluster space are intracluster planetary nebulae, rather than [O II] λ3727 galaxies at z ∼ 0.35 or Lyα sources at z ∼ 3.13. First, we confirm the nature of five “overluminous” [O III] sources that are postulated to lie in front of M87: by examining the composite spectrum of th...

Color gradients in early-type galaxies contain valuable clues about their formation and evolutionary histories and mechanisms. We examine color gradients in 1,700 early-type galaxies in 159 galaxy clusters spanning a redshift range of 0.05 to 0.2. We find that color gradients strongly depend on the environment where galaxies reside, with steeper color gradients in poor rather than rich clusters...

We bring you, as usual, the sun and moon and stars, plus some galaxies and a new section on astrobiology. Some highlights are short (the newly identified class of gamma-ray bursts, and the Deep Impact on Comet 9P/Tempel 1), some long (the age of the universe, which will be found to have the Earth at its center), and a few metonymic, for instance the term “down-sizing” to describe the evolution ...

Three hundred fifty three radio sources from the NRAO VLA Sky Survey (NVSS) (Condon et al. 1998) and the FIRST Survey (White et al. 1997), are detected in the areas of 179 Shakhbazian Compact Groups (ShCGs) of galaxies. Ninety three of them are identified with galaxies in 74 ShCGs. Six radio sources have complex structure. The radio spectra of 22 sources are determined. Radio luminosities of ga...